Water Pressure help please!

[Sychnant]

We are on a borehole, which connects to a pressure vessel, from which water comes to the house. Over the last couple of years this system has become unreliable, with the switch in the house tripping at least once a day. When this happens, it takes a while for the pressure to build back up and in the meantime taps etc run slow.

Recently we were able to afford to replace the pressure vessel, as it seemed to be this that was the problem. It was perfect for the first couple of weeks, and we could even have showers again! (If the pressure goes too low the power shower begins to run cold)

Now pretty much every time we have a shower, it is fine for a couple of minutes but the starts to run cold (usually just after you have rubbed in shampoo...) So you have to check the trip switch and wait for pressure to build back up.

Does anyone have any ideas as to what is going wrong? As it's driving me mad that I can't just have a quick shower :D

[PigletJohn]

Please describe this Trip Switch.

Is it the pump that stops? Anything else?

Where does the hot water come from? A cylinder or a combi?

[Sychnant]

Sorry, forgot I had posted here!

The trip switch is for the pump, yes.

The shower is a power shower so water comes through the normal way, same as the taps. If the pressure is too low because the pump is off, the shower runs cold as a safety thing.

Hot water comes from an immersion heater so I can heat it up separately for a bath. But I want the shower to work as it's so much quicker (and easier with long shampooy hair :/ )